Okay, after a month of usage, I have had a few issues.
First of all, the first day I got it the counter reset once from about 10000 keys or whatever I had back then to 0.
That didn't happen again, however, but today a key which had about 700000 presses last time I checked should've gotten to about 800000 now, but when I checked it went down to 237000, in line with some other keys which had about the same value, and these other keys I don't think that they were so close in value to each other before.
Then, some of the blocked keys, namely XButton1 and 2, had 1-2 counts even though they're disabled. I set it back to 0 through the notepad, but they keep getting 1-2 counts again.
There may have been some other precision issues with the key counts, but they didn't stand out so I'm not sure whether it actually happened.
Because these issues happened so randomly and in a large amount of time they are hard to recreate and therefore probably unfixable. The only solution I can see with my nonexistent scripting experience is to implement the key counts and key exclusions into the app itself, because for some reason I think that it's related to the fact that the files are detached and it has to check for them instead of being inside the app.
Edit: My counter went down again from 3 million and something to 2.7 million and I think that it will keep getting stuck here. I was thinking that it could be because of not having access to modifying it, but I do and in addition I haven't changed anything ever since I got the app.